title: Aptamer-directed lanthanide chelate self-assembly for rapid thrombin detection.
abstract: We report a sensitive assay method for homogeneous thrombin detection. The method is based on lanthanide chelate complementation, where the luminescent complex is split into two separate label moieties, which are intrinsically non-luminescent. A luminescent mixed chelate complex is formed only when the label moieties are brought into close proximity directed by two separate binding events of aptamers to the analyte. This results in high specificity in signal generation while time-resolved fluorescence detection eliminates the short lifetime autofluorescence, which is inherent to many homogeneous assays and limits their applicability. The developed method is also very rapid as the maximum signal is obtained in just five minutes. Lanthanide chelate complementation can be applied for the detection of other proteins when two binders recognizing separate epitopes of the analyte are available.
authors.affiliation: Department of Biotechnology, University of Turku, Tykistökatu 6 A 6th floor, FI-20520 Turku, Finland. henna.pakkila@utu.fi
authors.forename: Henna
authors.initials: H
authors.lastname: Päkkilä
authors.forename: Sami
authors.initials: S
authors.lastname: Blom
authors.forename: Kari
authors.initials: K
authors.lastname: Kopra
authors.forename: Tero
authors.initials: T
authors.lastname: Soukka
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D002614:Chelating Agents / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D005240:Feasibility Studies; D006801:Humans; D007700:Kinetics; D008024:Ligands; D009841:Oligonucleotides / Q000235:genetics / Q000378:metabolism; D013194:Staining and Labeling; D013917:Thrombin / Q000032:analysis* / Q000378:metabolism; D013997:Time Factors
chemical_list: D052157:Aptamers, Nucleotide; D002614:Chelating Agents; D008024:Ligands; D009841:Oligonucleotides; D005063:Europium; D013917:Thrombin